That little beep could be telling you something

Last Thursday night while lying in bed, I heard a faint beeping sound. We had been out earlier in the evening with friends. While I usually try to eat healthy, I had indulged in too much fried food and I had two glasses of wine, so I was feeling heavy and sluggish. Without worry and in that dreamy, almost asleep state I tried to figure out where the sound was coming from. As it was one of the rare warm nights in the Bay Area and our window was open, I figured it must be a truck backing up somewhere in the distance and the sound just traveled. Now that I had the noise categorized, I drifted off to dreamland.

But the next morning, while having a cup of coffee heard the sound again. The first thing I did was check my laptop... then I checked Phillip's laptop, then I checked the coffee maker. Then, as I was walking down the hall to check the alarm clocks, I remember the sound from last night and at that same moment realized the sound was coming from me. What a strange feeling.

This is my first beeping experience and it is not at all what I thought it would sound like. I thought it would be more of an English emergency siren. When I had to go in for the Fidelis lead check up (yes, I have one of those) they played the alarm for me and it was a two toned sound, like an English Emergency siren. This is not that sound at all. It is a single tone, off/on beep. And it was in my chest. Weird.

My ICD is only three years old. I don't get paced and there had been no previous indications that my battery was getting low. However, I do have a lead that has been recalled by the manufacturer, that is always a concern.

I called my cardiologist’s office, explained the alarm sound and they had me send in a carelink report (Medtronic’s remote monitoring system). They told me there would be a delay, but they would get the information as quickly as they can and call me back. About an hour later, the nurse called and told me that the impendence levels had changed and that I needed to come in immediately. They didn’t have to tell me why. I understood. I knew the monitoring on the recalled lead has be set so that it will trigger an alarm if there is a change as that is the first signal that the lead has fractured. A fractured lead can cause a “noise” in the system that the device can read as an arrhythmia. This could lead to the device delivering a shock when I don’t really needed, an inappropriate shock.

What threw me was the tone of the alarm. Since this is coming from inside your body, the sound is a little muted, but is was audible. As I mentioned already, the alarm they demonstrated for me was a two tone, high/low sound. But the alarm I heart was a single pitch, off/on sound. I am still not sure why that was different, but the alarm got my attention, I called the doctor and the doctors had me come into the office. In the end it didn’t matter which sound it was, it worked as it should have to help me avoid inappropriate shocks.

Hear the alerts of a Medtronic ICD:

• Low alert or high alert.

Alternating High/Low or On/Off tones:

Your ICD has detected an alert condition (low battery, abnormal lead impedance, electrical reset condition, etc.) This tone will last for 30 seconds (in older models) or 10 or 20 seconds (in newer models). You should contact your physician if you hear this tone. In the vast majority of cases this is not an emergency or life threatening condition—but it is important to find out what is going on. The alternating tone alarm will never go off just once. It will go off regularly at consistent intervals until the ICD is interrogated at the clinic and the condition that triggered it is resolved in some way. Most commonly the alarm will go off daily at the exact same time each day. This time is programmable and they likely told you when it would be or maybe even let you select it when they set up your device.


• No condition.

Steady tone at one fixed pitch:

Everything is OK. Indicates that a magnetic field have been detected by the ICD. The tone will last for 30 seconds (in older devices) or 10 or 20 seconds (in newer devices). Every time the ICD detects the magnetic field the alarm will re-sound. During the time your ICD is in the magnetic field, it is DISABLED (shocks are TURNED OFF). When your ICD leaves the field, everything returns to normal (if you are no longer hearing the alarm, you have left the field).

There are several reasons for this ICD feature. First, if for some reason your ICD needs to be temporarily shut off (for example, if you're having surgery), then this tone would let doctors know that when they place a magnet over the ICD they have in fact disabled the ICD. Second, it is a way to check that the ICD is OK without having to go to the clinic—this feature is being used for checking the Medtronic Marquis devices that are affected by the battery recall. They also try to hear this All-OK tone after a surgery or procedure in order to verify that their equipment didn't damage your ICD.